Statement of the Technical Field
The present invention relates to calendaring systems and more particularly to scheduling recurring events in calendaring systems.
Description of the Related Art
Calendaring systems have formed the core component of personal information management software and firmware applications for decades. Initially, a mere calendar display, modern calendaring systems provide scheduling and alarm functions in addition to full integration with contact management, time entry, billing and project management applications. The typical calendaring application minimally provides a mechanism for scheduling an event to occur on a certain date at a certain time. Generally, the event can be associated with a textual description of the event. More advanced implementations also permit the association of the scheduled event with a particular contact, a particular project, or both. Furthermore, most calendar applications provide functionality for setting an alarm prior to the occurrence of the event, as well as archival features.
One important feature of the calendaring system includes the ability to schedule a recurring event without requiring the end user to individually set an event on each recurring date. For example, where a meeting is to occur every week on a particular time over the course of several months, the end user can schedule the event as recurring every week at the particular time for the course of the several months. The calendaring system, in turn, can schedule each event in an automated fashion based upon the recurring information. Advantageously, the end user subsequently can modify any one of the recurring events, or the end user can apply a single modification to all of the recurring events responsive to which the calendaring system can apply the single modification to all of the recurring events in an automated fashion.
In recent years, computing has changed from a centralized model to a distributed model. Vast computer communications networks now couple together select users across the enterprise. Leveraging the wide reach of the modern enterprise, calendaring systems can incorporate multiple users and the events scheduled by multiple users. In particular, “groupware” oriented calendaring systems can permit one user to view and schedule events of other, remotely positioned users. To further provide interoperability between different types of calendaring systems, entire specifications have been developed to accommodate the distributed and disparate nature of the calendaring world. RFC2445 entitled “The Internet Calendaring and Scheduling Core Object Specification (iCalendar)” represents one such effort.
Notably, distributed and interoperable calendaring systems, like their stand-alone progeny, support the establishment of recurring events without requiring the end user to set each individual recurring event manually. Yet, more recent calendaring implementations no longer simply automate the process of setting multiple events specified by as recurring in nature. Rather, to conserve storage space, recurring events can be stored as a single event described as recurring in nature. More particularly, in order to optimize for space, the storage model employed by advanced calendaring systems stores only the event data and the recurrence rule. The actual event instances can be calculated dynamically when a request is processed to retrieve events within a certain date range.
Importantly, modification to a recurring event can be applied universally, to single instances of the recurring event, to past instances of a recurring event, or to all future recurring events. As described in RFC2445, however, the modification of the recurring event can be applied internally to the recurring event. Specifically, the recurrence rule defined within the recurring event, itself, can include the modifications to the recurrence rule. Interpreting and applying a modification to a recurrence rule in the conventional model, however, can be difficult and problematic for the uninitiated. Accordingly, it would be preferable to incorporate a simplified system, method and apparatus for applying modifications to recurring events in a calendaring system.